1. Field of the Invention
The present invention relates to a process for producing an N-alkyl-N-methylamine or an N-alkenyl-N-methylamine.
Aliphatic amines produced from tallow, coconut oil or palm oil are important intermediates for household and industrial products. Particularly aliphatic secondary amines such as N-alkyl-N-methylamine and N-alkenyl-N-methylamine are converted into quaternary ammonium salts and the like, and widely used as a raw material for softeners and antistatic agents and as a base material for conditioners.
2. Description of the Related Art
Aliphatic secondary amines have been produced from a fatty acid via a nitrile or by a process wherein a higher alcohol is aminated (see U.S. Pat. No. 4,792,622). Although only secondary amines having symmetrical alkyl chains (two alkyl chains which are identical with each other) can be produced in the former process, secondary amines having asymmetrical alkyl chains can be obtained by reacting a long-chain alcohol with a long-chain primary amine in the latter process (see Japanese Patent Laid-Open No. 202854/1990). However, even by the latter process, an efficient production of an N-(long-chain alkyl)-N-methylamine wherein one of the alkyl chains is a methyl group is difficult, because an N,N-di(long-chain alkyl)-N-methylamine is formed in a large amount as a by-product.